Rakudo Star 2012.02 released

2012-02-28

On behalf of the Rakudo and Perl 6 development teams, I'm happy to announce the February 2012 release of "Rakudo Star", a useful and usable distribution of Perl 6. The tarball for the February 2012 release is available from <http://github.com/rakudo/star/downloads>.

In the Perl 6 world, we make a distinction between the language ("Perl 6") and specific implementations of the language such as "Rakudo Perl". This Star release includes release #49 of the Rakudo Perl 6 compiler [1], version 4.1 of the Parrot Virtual Machine [2], and various modules, documentation, and other resources collected from the Perl 6 community.

Here are some of the major improvements in this release over the previous distribution release.

The FatRat type is implemented, and Rat arithmetic now properly defaults to Num if the denominator is too big

Object hashes are implemented, and can be declared with the syntax my %h{Any} (for a hash with keys of type Any)

The <Some::Grammar::rulename> syntax is now implemented in regexes; <foo> can also be used to call predeclared lexical rules

Improvements to the reduction meta-operator (order of magnitude faster, some parsing issues fixed)

The <prior> regex built-in is now available, and matches whatever the last successful match matched

A $match.make(...) method is available to set the AST for a match object not stored in the $/ variable

Improved backtraces

This release also contains a range of bug fixes, improvements to error reporting and better failure modes. Many more exceptions are thrown as typed exceptions.

Due to continued evolution of and convergence with the Perl 6 spec, there are some changes to existing functionality that may affect your code:

You may no longer use the $.x form in submethods and attribute initializers, as per spec; use the non-virtual $!x instead.

The LHS of the xx operator is now thunked

.conjugate is now called .conj

Enumeration values .gist to just the key, not the full name

An empty Buf is now False in boolean context

Currently, we have maintained backwards compatibility with some changed pieces of syntax, but will drop them in an upcoming release:

"<...>" in proto regex bodies; now this should be written "*"

The use of "**" with a separator in regexes; this is now done by using "%" or "%%" on another quantifier

There are some key features of Perl 6 that Rakudo Star does not yet handle appropriately, although they will appear in upcoming releases. Some of the not-quite-there features include:

pack and unpack

macros

threads and concurrency

Unicode strings at levels other than codepoints

pre and post constraints, and some other phasers

interactive readline that understands Unicode

non-blocking I/O

much of Synopsis 9

There is a new online resource at http://perl6.org/compilers/features that lists the known implemented and missing features of Rakudo Star 2012.02 and other Perl 6 implementations.

In many places we've tried to make Rakudo smart enough to inform the programmer that a given feature isn't implemented, but there are many that we've missed. Bug reports about missing and broken features are welcomed at <rakudobug@perl.org>.

See http://perl6.org/ for links to much more information about Perl 6, including documentation, example code, tutorials, reference materials, specification documents, and other supporting resources. An updated draft of a Perl 6 book is available as
<docs/UsingPerl6-draft.pdf> in the release tarball.

The development team thanks all of the contributors and sponsors for making Rakudo Star possible. If you would like to contribute, see <http://rakudo.org/how-to-help>, ask on the perl6-compiler@perl.org mailing list, or join us on IRC #perl6 on freenode.